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Master Lock S3900 Stainless Steel Pneumatic Valve Lockout

The Master Lock No. S3900 Pneumatic Lockout Device features:

  • Stainless steel construction for corrosion resistance
  • Fits virtually all male pneumatic fittings.
  • Pevents pneumatic fitting from being connected to pressurized air source.
  • Works with lockout hasps for multiple worker lockout situations.
  • Can lockout up to 6 pneumatic devices
  • Accommodates ¼ in, 5/16 in, 3/8 in, 7/16 in, ½ in, 9/16 in, 5/8 in, 13/16 in connections
  • Accepts up to 2 padlocks or lockout hasps for multiple worker lockout
  • Accepts any Master Lock or American Lock safety padlock with shackle diameter up to 9/32 in


  • Width:1-3/8"
  • Length: 7-3/4"
  • Thickness: 1/8" (33 x 185 x 3.2mm)


  • AIMS SKU A0086918
  • Brand Master Lock
  • Model Number S3900
  • Barcode Number 71649239649
SKU: A0086918 On Sale

Master Lock Pneumatic Lockout - Stainless Steel

Master Lock Pneumatic Valve Lockout Stainless Steel

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